Complete trisomy 13

**Definition:** Trisomy 13 is a chromosomal anomaly caused by the presence of an extra chromosome 13 and is characterised by brain malformations (holoprosencephaly), facial dysmorphism, ocular anomalies, postaxial polydactyly, visceral malformations (cardiopathy) and severe psychomotor retardation.

**Inclusions:** - Patau syndrome